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MIX DESIGN and MECHANICAL CHARACTERIZATION of STABILIZED COMPRESSED EARTH BLOCKS and ASSEMBLIES for the JEMEZ PUEBLO in NEW MEXICO Nicole B

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MIX DESIGN and MECHANICAL CHARACTERIZATION of STABILIZED COMPRESSED EARTH BLOCKS and ASSEMBLIES for the JEMEZ PUEBLO in NEW MEXICO Nicole B University of New Mexico UNM Digital Repository Civil Engineering ETDs Engineering ETDs Fall 12-2016 MIX DESIGN AND MECHANICAL CHARACTERIZATION OF STABILIZED COMPRESSED EARTH BLOCKS AND ASSEMBLIES FOR THE JEMEZ PUEBLO IN NEW MEXICO Nicole B. Trujillo University of New Mexico Follow this and additional works at: https://digitalrepository.unm.edu/ce_etds Part of the Civil and Environmental Engineering Commons Recommended Citation Trujillo, Nicole B.. "MIX DESIGN AND MECHANICAL CHARACTERIZATION OF STABILIZED COMPRESSED EARTH BLOCKS AND ASSEMBLIES FOR THE JEMEZ PUEBLO IN NEW MEXICO." (2016). https://digitalrepository.unm.edu/ ce_etds/147 This Thesis is brought to you for free and open access by the Engineering ETDs at UNM Digital Repository. It has been accepted for inclusion in Civil Engineering ETDs by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected]. Nicole Bernadette Trujillo Candidate Civil Engineering Department This thesis is approved, and it is acceptable in quality and form for publication: Approved by the Thesis Committee: Dr. Mahmoud Reda Taha , Chairperson Dr. John Stormont Tom Bowen i MIX DESIGN AND MECHANICAL CHARACTERIZATION OF STABILIZED COMPRESSED EARTH BLOCKS AND ASSEMBLIES FOR THE JEMEZ PUEBLO IN NEW MEXICO by NICOLE BERNADETTE TRUJILLO B.A.E, ARCHITECTURAL ENGINEERING, THE PENNSYLVANIA STATE UNIVERSITY, 2012 M.S., CIVIL ENGINEERING, UNIVERSITY OF NEW MEXICO, 2016 THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science Civil Engineering The University of New Mexico Albuquerque, New Mexico December, 2016 ii ACKNOWLEDGEMENTS I wish to thank my advisor and committee chair Dr. Mahmoud Taha for his guidance on this research and time spent reviewing my thesis. Thank you for offering me the opportunity to work on this project. I would also like to extend my gratitude to my committee members, Dr. John Stormont and Tom Bowen. Thank you both for your guidance and involvement in this research. I would like to thank my loving husband, Humberto for his patience and support. Even though we were hundreds of miles away, you were always there when I needed you. You encouraged me to complete my graduate degree and pushed me to achieve my goal. Thank you to my parents for their unfailing support and continuous encouragement throughout my years of study. I would especially like to thank them for the time spent supporting me on this project. Mom, for your constant love, immeasurable sacrifices, and faith in me. Dad, for teaching me to stay focused and to strive to reach my potential. To my sister, brother, grandparents and godparents, thanks for your support and unconditional love. Thank you to all my family and friends. I would like to thank Dr. Eric Peterson at the Department of Earth and Planetary Sciences for conducting the XRD testing and his assistance in providing the mineralogy presented in this thesis. I would also like to thank Dr. Adrian Brearley, Professor at the Department of Earth and Planetary Sciences, for providing me with the SEM data presented in this thesis. I express my gratitude to Mr. Francisco Uvina, Lecturer in the School of Architecture and Planning for sharing his knowledge about adobe and compressed earth block construction. iii I would like to express my gratitude to the many people who helped me in the UNM Structural Lab. Kenny Martinez for training me how to use laboratory equipment, assisting me in obtaining materials for various tests, and helping me set up experiments in the laboratory. I would like to thank Dr. Mehmet Emiroglu for all of his advice, guidance, and assistance in the lab, especially with the wall testing. I am grateful for all the assistance from Nicholas Martinez, Sumanth Doddikindi, Mohamad Hallal, and Conner Rusch who helped in performing various testing in the lab. I would also like to thank Jason Church from the Mechanical Engineering Machine Shop for machining many apparatuses for use in my experiments. I would like to thank George Shendo, Production Manager and David Chinana, Assistant Production Manager from the Jemez Community Development Corporation for delivering SCEBs to UNM and for building the SCEB wall panels. I am grateful for the financial support provided by the Jemez Community Development Corporation towards this project. iv MIX DESIGN AND MECHANICAL CHARACTERIZATION OF STABILIZED COMPRESSED EARTH BLOCKS AND ASSEMBLIES FOR THE JEMEZ PUEBLO IN NEW MEXICO by Nicole Trujillo B.A.E., Architectural Engineering, The Pennsylvania State University, 2012 M.S., Civil Engineering, University of New Mexico, 2016 ABSTRACT Earthen structures have a long architectural and cultural heritage in New Mexico. Similar structures are evident around the world. With the current depletion of natural resources and high cost of materials, compressed earth block construction offers a sustainable building material alternative. Stabilized compressed earth blocks (SCEB) are compressed earth blocks with additives such as, hydrated lime or Portland cement to protect the earth block from absorbing water. SCEBs are being produced using native soils for residential construction on the Jemez Pueblo in New Mexico. The primary goal of this research is to enable production of SCEBs with native soils from the Jemez Pueblo. The objectives of this research are to identify suitable local soils to be used to develop a compressed earth block mix design, compare the mechanical characteristics of SCEB to commercial adobe blocks, and investigate the mechanical behavior of SCEB prism and wall assemblies. Close to 50 native soil locations at the Jemez reservation in New Mexico were investigated. These soils were classified according to the Unified Soil Classification System (USCS) considering their grain size distribution, plasticity limit and swelling potential. A method for down selection of the soils suitable for compressed earth block v production was developed. In addition, the clay mineralogy of the suitable soils and soil mix designs were determined using X-ray Diffraction (XRD) and Scanning electron microscopy (SEM). SCEB mix design included two selected native soils, two sands and either Type S hydrated lime or Type II Portland cement. These materials were mixed to fabricate SCEBs of nine different SCEB mix designs. Compressive and flexural strength tests of the SCEBs were performed and compared to commercial adobe blocks. Tests to determine water absorption characteristics in SCEBs including initial rate of absorption, total absorption and sorptivity were also carried out. The mechanical and absorption characteristics of SCEBs were correlated to the mix design and the native soil classification. The ratio of clay and sand in the compressed earth block mix has a significant correlation with the mechanical and absorption characteristics of SCEBs. The results from all the testing showed that an optimum mix design was found for the nine blocks evaluated. SCEB assemblies, including prisms and wall panels were produced with standard type S mortar. Prisms made of SCEB units were tested to determine the compressive strength, bond strength, and shear strength. The time-dependent creep of the SCEB prism at 56 days of age was also evaluated. These measurements showed that creep displacement has a significant effect on the total displacement of the prism assembly. The approximately 570 mm x 570 mm (22 in. x 22 in.) SCEB wall panels made of the optimum SCEB were tested under in-plane shear using a diagonal compression test. The results of the diagonal compression test show that the SCEB wall assembly obtained a lateral strength comparable to rammed earth. vi The results showed that some SCEBs have higher compressive and flexural strengths than commercial stabilized adobe. SCEBs provide a resilient, sustainable building material and are suitable for use in residential construction for the Jemez Pueblo in New Mexico. vii TABLE OF CONTENTS ACKNOWLEDGEMENTS ............................................................................................... iii ABSTRACT .........................................................................................................................v TABLE OF CONTENTS ................................................................................................. viii LIST OF FIGURES ......................................................................................................... xiii LIST OF TABLES .............................................................................................................xx CHAPTER 1: INTRODUCTION ........................................................................................1 1.1 Background ............................................................................................................... 1 1.2 Motivation ................................................................................................................. 2 1.3 Research Objectives .................................................................................................. 2 1.4 Summary of Work..................................................................................................... 3 1.5 Outline....................................................................................................................... 4 CHAPTER 2: LITERATURE REVIEW .............................................................................5 2.1 Introduction ..............................................................................................................
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